Rename icons for typst mimetype

Boris Jurcagarequested to merge
demaestus/breeze-icons:fix_typst_icon_name into master

Typst icon names contained incorrect MIME subtype. Change text-x-typst.svg to text-vnd.typst.svg.

Some applications failed to find the Typst icon as its filename does not match the official MIME subtype for Typst.

Merge request reports